Chapter 4: From Conception to Birth

A protein is composed of a sequence of chemicals, a long string of building blocks called amino acids.proteins: adenine, thiamine, cytosine, and guaninepairings: A-T, T-A, C-G, and G-C

Deoxyribonucleic AcidThe chemical composition of the molecules that contains the genes, which are the chemical instructions for cells to manufacture various proteins.

One of the 46 molecules of DNA (in 23 pairs) that virtually each cell of the human body contains and that, together, contain all the genes.

Every human cell (excluding egg or sperm cells) has 22 matching chromosome pairs, plus a 23rd pair of sex chromosomes that determine whether a person is male or female

The full set of genes that are the instructions to make an individual member of a certain species.Thus, the human genome contains hundreds of thousands of molecules, forming about 20,000 genes on 46 chromosomes, using 3 million base pairs of 4 chemicals to instruct production of 20 amino acids to create proteins that make each person unique, yet similar to all other humans.

Twins who originate from one zygote that splits apart very early in development. (Also called identical twins.)

Twins who are formed when two separate ova are fertilized by two separate sperm at roughly the same time.

(Also called fraternal twins.)

A reproductive cell; that is, a sperm or ovum that can produces a new individual if it combines with a gamete from the other sex to make a zygote.

2 million

determines sex.XX - femaleXY - male

The observable characteristics of a person, including appearance, personality, intelligence, and all other traits.

The genetic makeup of an individual that is invisible to the naked eye

A condition in which a person has 47 chromosomes instead of the usual 46, with 3 rather than 2 chromosomes at the 21st site. People with Down syndrome typically have distinctive characteristics, including unusual face features, heart abnormalities, and language difficulties.

Germinal PeriodEmbryonic PeriodFetal Period

Germinal Period - First 2 weeksEmbryonic Period - Third to Eighth weekFetal Period - Ninth until birthLongest - Fetal Period

About 22 weeks after conception, at which a fetus may survive outside the mother's fetus if specialized medical care is available.

A surgical birth, in which incisions through the mother's abdomen and uterus allow the fetus to be removed quickly, instead of being delivered through the vagina.

A woman who helps with the birth process. Traditionally in Latin America, a doula was the only professional who attended the childbirth.

Now doulas are likely to arrive at the woman's home during early labor and later work alongside a hospital staff.

Agents and conditions that can harm the prenatal brain, impairing the future child's intellectual and emotional functioning.About 20 percent of all children have difficulties that could be connected to behavioral teratogens, although the link is not straightforward.

oxytocin

A quick assessment of a newborn's health based on the baby's color, heart rate, reflexes, muscle tone, and respiratory effort. The scores are 0-2. It is performed twice, a minute after birth and five minutes after birth.

Color: Blue, paleHeartbeat: AbsentReflex irritability: No responseMuscle tone: Flaccid, limpRespiratory effort: absent

Color: Body pink, extremities blueHeartbeat: Slow, <100Reflex irritability: GrimaceMuscle tone: Weak, inactiveRespiratory effort: Irregular, slow

Color: Entirely pinkHeartbeat: Rapid, >100Reflex irritability: Coughing, sneezing, cryingMuscle tone: Strong, activeRespiratory effort: Good, baby is crying

7: The infant needs helpBelow 4: A neonatal pediatrician rushes to the delivery room to provide emergency careMost score 8 or 9rare: 10

Low Birthweight (LBW) - a body weight at birth of less than 5 1/2 pounds.Very Low Birthweight (VLBW) - a body weight at birth of less than 3 pounds, 5 ounces.Extremely Low Birthweight (ELBW) - a body weight of less than 2 pounds, 3 ounces.

-Reflexes that maintain oxygen supply-Reflexes that maintain constant body temperature-Reflexes that manage feeding

Breathing reflexadditional: hiccups, sneezes, thrashing (moving the arms and legs about) to escape something that covers the face

Crying, shivering, tucking in their legs close to their bodies when coldPush away and stay still when hot

-Sucking reflex to suck anything that touches their lips-Rooting reflex that causes babies to turn their head toward anything that brushes against their cheeks-Swallowing reflex-Crying-Spitting up

Agents and conditions, including viruses, drugs, and chemicals, that can impair prenatal development and result in birth defects or even death.

The fetus is exposed to a terotogen

A situation in which a certain teratogen is relatively harmless in small doses but becomes harmful once exposure reaches a certain level (the threshold).Examples: Vit A, > 50,000 units/day

Symptoms of pregnancy and birth experienced by fathers

A new mother's feelings of inadequacy and sadness in the days and weeks after giving birth (called baby blues in the mild version and postpartum psychosis in the most severe form).

A cluster of birth defects, including abnormal facial characteristics, slow physical growth, and retarded mental development, that may occur in the child of a woman who drinks alcohol while pregnant.FAS may later cause fetal alcohol effects (FAE) leading to hyperactivity, poor concentration, impaired spatial reasoning, and slow learning.